The long-term objective of this program is to develop a drug for the treatment of memory deficits associated with aging and Alzheimer's disease. Loss of working memory represents the core early symptom of Alzheimer's disease. AIT-082 is a unique purine derivative that specifically enhances working memory in normals animals, restores working memory deficits in aged animals and stimulates neuritogenesis in PC12 cells in a manner similar and additive to the effects of nerve growth factor (NGF). The aims of this proposal are to (1) establish the psychopharmacological profile and pharmacokinetics of absorption and distribution of AIT-082, (2) evaluate the effect of AIT-082 on age- induced memory deficit in C57B1/6 mice and determine if AIT-082 can prevent the development of these deficits, (3) determine if AIT-082 exerts its NGF-like activity through a guanylate cyclase mediated mechanism or if some other second messenger system is operative, (4) evaluate AIT-082 in a passive avoidance memory model in rats and mice, and (5) determine the activity of AIT-082 in vivo to prevent or reverse the amnestic activity of specific neuro-receptor blocking agents. AIT- 082 can potentially mimic NGF's biological activity by means of a simple organic molecule that passes the blood-brain barrier.